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Estructuras ordenadas en aleaciones binarias de renio a partir de cálculos de los primeros principios
Ohad Levy1, Michal Jahnátek, Roman V Chepulskii
1Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, USA.
Journal of the American Chemical Society
|December 15, 2010
Resumen
Los datos de aleaciones de renio son escasos. Los cálculos exhaustivos de los primeros principios predicen estructuras estables en 20 de los 28 sistemas de metales de transición de renio, revelando muchos compuestos no reportados y sugiriendo la necesidad de una comprensión revisada.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Materiales computacionales Ciencia de la ciencia.
- Química del estado sólido.
Sus antecedentes:
- El renio (Re) es crucial para la catálisis y las superaleaciones.
- Los datos experimentales y computacionales existentes sobre aleaciones Re binarias son limitados.
- Solo una fracción de los sistemas Re de metales de transición están bien caracterizados.
Objetivo del estudio:
- Investigar exhaustivamente la estabilidad de fase de las aleaciones binarias de metales de transición de Renio.
- Para predecir estructuras ordenadas estables utilizando cálculos teóricos.
- Para identificar nuevos compuestos potenciales y revisar la comprensión actual de los sistemas de aleación Re.
Principales métodos:
- Utilizó cálculos de alto rendimiento basados en los primeros principios.
- Investigó 28 sistemas binarios distintos de Renio y metales de transición.
- Comparó las predicciones teóricas con los datos experimentales existentes.
Principales resultados:
- Se predijeron estructuras ordenadas estables en 20 de los 28 sistemas Re. investigados.
- Reproducido todos los compuestos conocidos en sistemas previamente caracterizados.
- Se identificaron varios compuestos estables potencialmente no reportados.
- Identificó 8 sistemas donde no se predice la formación de compuestos estables.
Conclusiones:
- Las predicciones teóricas revelan un número significativamente mayor de sistemas de aleación Re formadores de compuestos de lo que se conocía anteriormente.
- Se justifica una revisión extensa de la comprensión actual de los diagramas de fase de las aleaciones de Renio.
- Los enfoques teóricos y experimentales combinados son esenciales para la caracterización precisa de las aleaciones.
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